Electronic copiers, photofinishing devices, inkjet printers and/or other forms of printers are commonly used to render multi-page compilations of printed materials such as multi-page documents, sequences of images and the like. Typically, it is desired that the pages of such documents be presented to the user in an orderly and sequential fashion. Accordingly, automatic collation and arrangement of printed material is a highly desirable feature in printers.
Some printers incorporate advanced collating systems that actively work to arrange printed pages to provide features such as multi-document collation, stapling, folding and the like. For example, U.S. Pat. No. 4,696,591 to Boyden, issued Sep. 29, 1987, entitled “Fan Folded Printer Output Collector,” describes a printer output collector useful in printers that print on so-called fan folded paper. In this patent a printer having a fan folded output is provided with an output catching tray which cantilevers upwardly at an angle of 35-55 degrees from the printer output. The tray includes side walls defining a bottom which bears on the top of the printer. The sidewalls each define integrally formed hooks for catching onto the printer at any bar of fastening disposed in the area of the output. These hooks enable the cantilevered support to occur. At the bottom of the tray, an arcuate and cam-like surface is disposed against the printer output. This cam-like surface takes horizontal output from the printer and causes it to pass upwardly over its surface. The cam surface extends from an angle in the range of 45 degrees in vicinity of the printer to a slope beyond horizontal at the bottom of the paper catching tray. The end of the cam and the bottom of the paper catching tray form a notch. The paper catching tray extends upward from the notch at an angle between 30 to 60 degrees, the full length of the fan fold paper, and is preferably provided at the upper end thereof with a paper stop. In operation, fan folded paper output from the printer is fed to the tray, typically to the notch at the end of the cam surface and the beginning of the upwardly extending tray. Thereafter, when printer output occurs, the columnar strength of the paper combined with the natural weight of the paper as it lies on the tray surface causes a fan fold layering of the paper catching tray.
The system provided in the '591 patent allows a user to view the printed output of the printer soon after printing which in turn allows real time print monitoring and job interruption where necessary. However, it will be appreciated that this system requires a printer that is capable of actively driving movement of the receiver medium even after printing is complete. EP 0 183 413 A2, to Prevignano, issued Aug. 1, 1990, describes a sheet feeder that can supply both cut sheets and continuous media for an office printing or typing machine. After printing such media is advanced by the printer against gravity into a collector tray. The collector tray simply receives such material.
However, such active driving systems can be costly and complex. What is needed therefore is a system that can collect printed mediums in a sequentially collated and orderly way but without actively driving the printed pages after printing.
There have been attempts to provide such systems. For example, U.S. Pat. No. 4,936,698 to Clyburn, issued Jun. 26, 1990, entitled “Printer Stand with Print-Out Catcher,” describes a printer stand that comprises a support base for holding a rear-ejection printer and a paper catcher mounted to the rear of the printer and extending rearwardly and upwardly therefrom. The catcher comprises a flat backer panel having bent-up side flanges and having a bent-up lower ledge for supporting the lower edge of a packet of sheets of paper resting against the backer panel. The catcher is mounted to the base for easy removal by providing a forwardly and downwardly extending slot at the rear of each side wall of the support base, into and out of which the panel can readily be slid; the side flanges are preferably spaced apart by only slightly more than the distance between the outer sides of the side walls, and the ledge is preferably at about right angles to the packer panel. The system provides stable support of the packet of sheets, is easily assembled and disassembled, and is inexpensively made from a single metal sheet by bending up the side flanges and the ledge. The system, however, is best adapted to receive and collate sheet mediums having a fixed length.
WO 2005/070674 to King et al., published on Aug. 4, 2005, entitled “A Printer Unit Employing Vertically Disposed Media Storage and Collection Areas” describes a printer unit employing substantially vertically disposed media storage and collection areas. In this system a transport device is provided to transport print media through a delivery path which passes through an angle of at least 140 degrees and preferably 180 degrees from the supply area to the collector area. A foot portion is arranged to project into the substantially vertical path of the ejected sheets and has a contact surface that is arranged to contact a leading edge of the sheets to stop movement thereof along the substantially vertical path. The contact surface is arranged to urge the sheets toward the collection surface for collection, such as by having an angle that is inclined from the vertical path. Optionally, an outlet from which the sheets are ejected can be arranged with respect to the foot portion so that the ejected sheets are allowed to fall under gravity to assume the substantially vertical path. To retain media within the storage area, the guide ribs are shaped to impart a curvature of the media.
While the '674 publication provides a good solution for organizing printed media, this solution requires that the printing system have a substantially vertical profile which may not be suitable or desirable in many applications. Further, it will be appreciated that many printers and printing technologies use a generally horizontally configured print head, which is not compatible with such a vertical configuration.
Further, as illustrated in FIG. 1, a printer 8 of the kind that is described in the '674 publication will store previously printed sheets 10 in a vertical stack in storage area 12. Such stacks of previously printed sheets are stored with trailing edges 14 thereof arranged in a manner that can interfere with the movement of the leading edge 16 of a recently printed sheet 18 after recently printed sheet 18 leaves the nip between printhead 17 and a platen 19 or is otherwise released from the positional control by printer 8. This can cause damage to edges 14 or 16, can disrupt the arrangement of previously printed sheets 10 by causing previously printed sheets 10 to move, or by inserting recently printed sheet 18 within previously printed sheets 10. In certain circumstances, recently printed sheet 18 could be held in print head 17 in a manner that can interfere with future printing operations.
What is needed, therefore, is a print storage and collation system that can be used to provide a more horizontal profile while also providing greater reliability and without requiring active driving of the recently printed sheets.